Concrete-mixers



E. w'. BRACKENBURY.

comma mxsn. APPLICATION f-ILED JUNE l9, I914- RENEWED APR. 15 1920.

1,350,293, Patented Aug. 24, 1920.

2 suns-swan I.

WITNESSES \NVENTQR V m awb'zl ATTORNEY Y E. w. BRACKENBURY.

CONCRETE MIXER. -APPucAT|0N FILED JUNE 19. 1914. RENEWED APR. 15. 1920.

1 350,293 Patented Aug. 24; 1920.

2 suns-sun 2.

Min-messes 4 lNvENToR AT'Tonurr the arrow shown in Fig. 1.

ra wann w. BRACKENBURY, or

MILWAUKEE, wIscoNsIN, AssIeNoaro THE '1. L.

SMITH COMPANY, or MILWAUKEE, wIsCoNsIN, A CORPORATION or WIsCoNsIN.

CONCRETE-MIXERS.

Application filed June 19', 1914, Serial No.

tilting type; and the objects of my invention are, to provide blades which have an efficient mixing action and which will lift all the material in the drum to the discharge chute, I to provide a chute for discharging the mixer, that may be quickly and easily operated, that may project a sufiicient d stance into the drum to produce a rapid d1scharge, that may drain into the drum when in nonoperative position, and that shall have all its operating connections outside of the drum. 7 I f I attain these objects by the mechanism illustrated in'the accompanying drawings, in which- I I Figure 1 shows a side elevation of the mixer drumwith the frame work and discharge chute'.

Fig. 2 shows an end elevation of the machine, part of the drum being shown in central vertical section to illustrate its interior form, anc I I I Fig. 3 shows a detail of construction. v

Referring to the drawings more in detail, themixer drum is designated by a. This drum-isrotated by means of its attached annular gear ring Z2, and is supported by the rollers c. 0., which engage the roller tracks old. The entire machine-is supported on a frame of which'c. e. are the longitudinal members.

. The material to bemixedis introduced to the drum through the feed opening f, and as the drum revolves this material is continually lifted and poured by the mixing buckets g. f l

The drum a is driven in the direction of Eachbucket consists of. a bottom plate'g extending from the shell toward the axis of the drum. The sides'of' the bucket 9 are substantially perpendicular to its bottom plate and are in- Speeification of Letters Patent. Patented Aug. 24, 1920. 846,056. Renewed April 15, 1920. Serial No. 374,201.

clined to' the axis ofthe drum, forming therewith an angle of about forty degrees, and an angle of about fifty degrees with the shell. A portion of the sides next to the shell and marked is formed perpendicular to the shell to avoid the acute angle which the sides would otherwise make with the shell and which would merely fill up with concrete. 9 is the open dischargeend of the bucket and g is theopen side through which the concrete is scooped in as the drum revolves in the direction of the arrow. Small inclined blades g? are attached to the parts g of the buckets and extend to the.

eads of the drum. They are attached to the open sides 9 of the buckets. Their function in mixing is to deflect stones into the buckets that might otherwise roll around .contmually in the corners of the drum, and

their function in i discharging is to extend Lthescooping action of the buckets over the entire width of the drum to increase the rapidity of gathering up the, last portions of concrete when the drum is nearly empty.

It might naturally be supposed that the buckets 9 should extend the entire width of the drum, but I have found the arrangement' here set forth the more efficient. While the drum is holding its full batch it is not necessary to lift the materials throughout the entire width of the drum, as such a large proportion of the material'is lifted that room is left in the wake of each bucket, so the material between 9 and the drum heads flows inward toward the medial plane -.of the drum to fill this space.

Further, the crowding cndwise mixing action of the sides 9 is more efiicient when their angle is steep. Also, the chance for concrete to collect in corners is reduced by leaving the space outside of g The mixture is discharged from the'drum by the discharge chute or spout h,-which is shown in its operative discharging'position in full lines, and in its inoperative position indotted lines in Fig.

This chute is supported by the-two uprights 70. 1a., to which the brackets Z are attached. The two arms m are pivotally attached to the brackets l at their inner ends by the pivot pins p, and at their outer ends are attached to' the ends of the bar n, to

plates or arms 0.

' This conical ring is attached which the spout h is attached by the two The spout is swung on its pivots p by either one of the handle bars 9 which are attached to the arms m by means of the Z-shaped plates r. The spout may also be operated from the feed side of the machine by means of the rod 2? which is pivoted at c to the arm 8 attached to the handle bar g, see Fig. 3. The spout is balanced on its pivotal axis by the counterweight w.

Thespout is prevented from swinging :too far into the drum by the Z pieces 1" engaging with the uprights 70 as shown in Fig. .3. Also, when the spout is swung out of the drum, the uprights 7c are again engaged by the 2 pieces r, the contact being made by the top edge of 7" instead of by its broad side.

The position of the pivots p of the discharge spout is limited by the following five considerations: .(1) The spout in discharging position must stand at an angle of about 3.5 degrees to the horizontal, (2), its re- .ceiving'end must extend under the deliver-Y 111g openings g of the scoops, and, (3), must not be substantially above the drums axis, (4) in its inoperative position the spoutmust stand with its tip end just .entering the drum and the spout still at an angle of 35 degrees to the horizontal, in or der that whatever concrete was on the spout when the discharge was stopped may run back into the drum. The foregoing considerations necessitate the pivot points being located between the planes of theheads of the drum, but, ('5), they must be exterior to the drum as the spout must be balanced by the weights w and parts of operative mechanism should not be placed where they will become coated with the concrete.

The head of the drum through which the discharge chute operates is formed with a conical ring (L1 projecting into the drum. to the straight head of the drum by the flange 6 .The object of this conical ring is to enable the aper 'ture through which the spout moves to be of smaller diameter than would be necessary if this aperture were placed in the plane of the straight head. The spout must stand at an angle of thirty-five degrees to'the horizontal in order that the concrete may slide down rapidly. The receiving end of the spout in the drum must have its major part below the axis of the drum, as otherwise the buckets 9 would be empty before they attained a sufficient height to discharge into the spout. This reentrant conical ring allows the spout V to project a sufficient distance into the drum v duce a rapid discharge,

at a proper height and proper angle to prowithout reducing the capacity of the drum by increasing the size of the discharge opening.

It will be understood that While I have shown the preferable embodiment of my in clined toward the interior provided with a discharge opening near the 1 axis of the drum, and an inclined discharge spout entering the drum in a position to cross'the plane of the discharge end of the drum .at a'point lower than the discharge opening, said discharge end ofthe drum being depressed to carry the discharge opening within the drumnearer to the medial plane of the drum. r

2.. In a concrete mixer, a rotary mixing drum having mixing and lifting blades and a discharge end movable therewith, a conical ring passing through an opening in the discharge end of the drum withits smaller end projecting within the drum .and forming a discharge opening in a plane closer to the medial plane of the drum than said discharge end of the drum, and an inclined discharge spout entering the drum through the discharge opening in a position .to cross the plane of the discharge end of the drum'at a point lower than the discharge opening.

3. A rotatable mixing drum containing a plurality of tapering scoops symmetrical in form and position as referred :to the medial plane of the drum, each scoop. having its wide end attached to the periphery of the drum, and its narrow end opening toward the axis of the drum, and supplemental blades of comparatively small height extending from the front edge of the sides of the scoops to thedrum heads and adapted and arranged to deflect material-at the bottom corners of the drum into the scoops.

4. A mixer, comprising, arotary drum having liftingland mixingelements therein, and provided at its discharge'end'with a conical ring having its smaller end projectits pivots located between the [planes in which the heads of the drum are located,

and supporting bearings for said pivots,

said pivots and bearings being located out 1 side of the drum and said spout being inof the drum when in an inoperative position.

6. A rotatable mixing drum having centrally located. tapering mixing scoops, at

tached at their larger ends to the periphery of the drum and their small ends Opening toward the drums axis, an inclined discharge spout adapted to extend into the drum in position to catch the discharge from said scoops, and a reentrant cone on the discharge end of the drum carrying the periphery of the discharge aperture toward the axis of the drum and toward the medial lane of the drum.

7. A rotatable mixing drum having centrally located tapering mixing scoo s, attached at their larger ends to the periphery of the drum and their small ends opening toward the drums axis, in combination with a pivotally mounted discharge spout having its pivotal axis located between the planes inwhich the heads of the drum are located and supported outside of the drum, said spout inclining downward and'inward to the drum when in inoperative position, and a conical ring on the discharge end of the drum entering the drum at the same inclination as the discharge spout when the latter is in its discharging position.

8. In a concrete mixer, a rotatable mixing drum having mixing and lifting blades therein, a pivotally mounted discharge spout having its pivots located between the planes of the heads and outside of the drum, said spout inclining downward and inward to the drum when in inoperative position, and a reentrant cone on the. discharge end of the drum carrying the periphery of the discharge aperture inward of the drum toward the medial plane thereof.

9. In a concrete mixer, a rotar mixin drum having mixing and lifting b ades an a discharge opening, a discharge spout pivotally supported outside of the mixing drum and between the planes containing the ends of the mixing drum to have an inclined discharge position in the drum and a removed inclined inoperative position in which it will drain into the drum, said spout in its discharge position entering the drum in a position to cross the plane of the discharge end of the drum at a point lower than the discharge opening, and said discharge end of the drum being depressed to carry the discharge opening within the drum.

Signed in the presence of two witnesses this tenth day of June 1914.

EDWARD W. BRACKENBURY.

Witnesses E. O. NANKTELOW, LILLIE SOHUMAGHER. 

